The Messenger of Allah ﷺ said, "Whoever relieves a believer of one of the hardships of this world, Allah will relieve him of one of the hardships of the Day of Resurrection. Whoever eases the burden of someone in difficulty, Allah will ease his burden in this world and the next. Whoever conceals the faults of a Muslim, Allah will conceal his faults in this world and the next. And Allah continues to aid His servant so long as the servant is aiding his brother."
قال رسول الله ﷺ: من نفس عن مؤمن كربة من كرب الدنيا نفس الله عنه كربة من كرب يوم القيامة. ومن يسر على معسر يسر الله عليه في الدنيا والآخرة، ومن ستر مسلما ستره الله في الدنيا والآخرة، والله في عون العبد ما كان العبد في عون أخيه.
Muslim narrated it in the chapter on remembrance (2699) through various routes from Abu Muawiya, from Amash, from Abu Salih, from Abu Hurairah, and mentioned it in a longer context than this. On this subject there is also what was narrated from Uqba bin Amir, who said, "I heard the Messenger of Allah say, 'Whoever conceals the private matter of a believer is as if he has revived a buried infant from her grave.'" This was narrated by Abu Dawud (4892) and Ahmad (1795), both from the hadith of Layth bin Saad, from Ibrahim bin Nushayt Khawlani, from Kaab bin Alqama, from Abu Haytham, from Dukhayn, the scribe of Uqba bin Amir, who said, I said to Uqba, "We have neighbors who drink wine, and I am going to call the guards for them so they can seize them." He said, "Don't do that, but rather admonish them and threaten them." He said, so he did, but they did not stop. He said, so Dukhayn came and said, "I forbade them but they did not stop, and I am going to call the guards for them." Uqba said, "Woe to you, don't do that, for I heard the Messenger of Allah say," and he mentioned it.In this chain is Abu Haytham, who is unknown, and there is also severe confusion in it, which Munziri pointed out in Mukhtasar Abu Dawud. So one cannot feel confident in grading it hasan, let alone sahih.Likewise, what was narrated from Ibn Abbas as a raised hadith is not sound, "Whoever conceals the private matter of his Muslim brother, Allah will conceal his private matter on the Day of Resurrection, and whoever exposes the private matter of his Muslim brother, Allah will expose his private matter until He disgraces him with it in his own house." This was narrated by Ibn Majah (2546). In its chain is Muhammad bin Uthman Jumahi Makki, who is daif by the agreement of the scholars.